Implantable medical devices frequently use set screws to secure a catheter into an electrical and/or non-electrical connection system to deliver a medical treatment therapy, i.e. pacemakers, defibrillator and neurostimulators. A torque wrench is used to engage and tighten this set screw. The torque wrench has a predetermined torque limit that prevents the set screw from damaging the catheter or medical device, rendering them unusable or un-removable.
While the torque wrenches that are currently used have limited tightening torque, they are not torque limited in the reverse (screw removal) direction. As a result, the wrench may accidentally apply a reverse torque as it is disengaged from the set screw and the set screw can become loosened, potentially causing a loss of electrical conduction or other malfunction of the medical device. Additionally, prior art torque wrenches do not have any indicator showing whether the wrench has been used to tighten a fastener to the prescribed torque.